The back and forth between Terence Crawford and Errol Spence Jr. advanced to another level Sunday night.

Crawford hadn’t talked much about his long-discussed showdown with Spence in recent months because Spence was recovering from injuries sustained during a one-car accident October 10 in downtown Dallas. Once Spence respectfully mentioned on Twitter why their fight hasn’t happened with Crawford’s sister, Latisha Crawford, her brother blasted the unbeaten IBF/WBC welterweight champion.

“So what’s been the [holdup] homie?,” Crawford Tweeted at Spence on Sunday night. “When I came to the division y’all all said I had to get a title first. Now you changed yo mind and talking about wrong side of the street. So I’m just here for another excuse what’s up.”

Crawford referred to Spence’s well-documented comment of the unbeaten WBO welterweight champion operating on “the wrong side of the street” because Crawford (36-0, 27 KOs) is promoted by Bob Arum’s Top Rank Inc. and has an exclusive contract to fight on ESPN. Spence is affiliated with adviser Al Haymon’s Premier Boxing Champions and has fought on Showtime and FOX Sports Pay-Per-View.

Prior to suffering facial lacerations and dental damage in the aforementioned accident, Spence stated that he wants to face PBC-affiliated welterweights, namely Manny Pacquiao and Danny Garcia, before pursuing a fight with Crawford.

“I’m ready when you ready,” Crawford Tweeted at Spence later Sunday night. “Matter of fact, I been ready before I even had a 147 LB fight. Like I been said you got these people fooled but not me. [Whenever] u get back right I’ll smoke you all you gotta do is sign the contract next and I’m on yo head.”

Spence (26-0, 21 KOs), of DeSoto, Texas, stated during a live interview with FOX’s Brian Kenny on December 22 that he plans to return to the ring either late in the spring or early in the summer. Spence, who’ll turn 30 on January 13, added that he doesn’t want a tune-up fight in his first appearance after the accident.

In the last Tweet in which he tagged Spence on Sunday night, the 32-year-old Crawford added, “And stop using f---ing promoters, managers and advisors for that weak ass excuse y’all doing they work for us y’all dumb mf if you really want a fight you tell them i don’t give two f--ks that’s who I want to fight. let yo nuts drop you say you yo own boss.”

Between the second and third Tweets in which he tagged Spence, the Omaha, Nebraska, native sent a Tweet directed at Spence’s supporters.

“Keep defending him,” Crawford stated, “because I’m tell all y’all now and I mean what I say when that day come when I knock him [out] all I want all y’all to keep that same energy because he gone cry in the car he wasn’t built for this sh-t I got over here just watch me show the world.”

Spence initially Tweeted late Sunday afternoon, “y’all can believe the bs if you want [I ain’t ducking] nothing.” Spence used a duck emoji in place of the word ducking.

Latisha Crawford responded with, “Make the fight then,” to which Spence replied, “It go both ways mrs.”

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.